The invention is based on a wiper apparatus. In a known wiper apparatus of this type (German patent disclosure DE 23 13 689 A1), the wiper blade that belongs to the wiper apparatus has a guide channel that is open toward a base body of the wiper strip, and in this channel, a hairpin-shaped securing spring is displaceable between a mounting position and a locking position. This securing spring is provided, for opening and closing a recess which is disposed in a coupling part on the wiper blade and which represents the bearing recess for the wiper arm pivot bolt. The securing spring is prestressed toward the rubber guide channel, so that to displace the spring, the friction between the rubber and the spring has to be overcome. On the one hand, it should be easy for the user to slide the spring, for instance when changing wiper blades, but on the other, the spring must reliably close the bearing recess in the channel wall during wiping operation, so that the wiper blade cannot become disconnected from the wiper arm unintentionally. These two mutually contradictory demands cannot both be met equally well.
In the wiper apparatus of the present invention, the pivot lever is moved in a smooth bearing point between its two operating positions, so that the desired position can be reached reliably without expending force.
To avoid unintended opening of the channel, the connection device is provided with a barrier element for locking the pivot lever in its locking position.
If the wiper arm has a U-shaped cross section on its free end, and each of the two ends of the pivot bolt is retained on one of the two legs of the U, then the coupling part of the wiper blade after being mounted on the wiper arm can have the free end of the wiper arm fitted over it in such a way that the coupling part is located between the two legs of the U of the wiper arm. The result is an especially low-height construction for the wiper apparatus.
Visual checking of the bearing point or for proper support of the pivot bolt in its bearing recess is made possible if the base of the U joining the two legs of the U is located on the end of the legs of the U remote from the wiper blade and ends at a distance from the pivot bolt.
To keep the wiper arm as short as possible, the pivot lever bearing point on the coupling part is disposed toward the guided end of the wiper arm at a distance from the bearing recess for the pivot bolt, and the pivot axis of the pivot lever is oriented at least approximately parallel to the hinge axis.
In a feature of the invention, the base of the U of the free end of the wiper arm extends past the pivot lever bearing point and ends between this bearing point and the hinge axis of the bearing recess. As a result, the pivot lever is blocked in its closing position, when the wiper apparatus is in the operating position, or in other words when the wiper blade is pressed against the window to be wiped.
To optimize bearing the bolt in the coupling part, the pivot lever in its locking position protrudes with an extension into the mounting channel and in the region thereof continues the jacket face of the longitudinal recess.
So that the extension, or the bearing face embodied on it, will be properly fixed, the pivot lever is provided with a stop, which in the pivot lever operating position cooperates with a counterpart stop of the coupling part.
A further reduction in the structural height of the wiper apparatus is attained if the coupling part is located on the band face, remote from the window of a bandlike, elongated, spring-elastic support element, on whose band face toward the window the wiper strip is disposed. A low structural height of the wiper apparatus is important especially in view of the tendencies of the wiper blade to lift away from the window, a tendency that can occur at high travel speeds.
To achieve an advantageous fastening of the coupling part to the support element of the wiper blade, the coupling part at least in some portions engages the two longitudinal side edges of the support element in clawlike fashion.
Especially good wiper blade guidance with simultaneous relief of the joint between the wiper arm and wiper blade is obtained if, in a further feature of the invention, the width of the coupling part, measured transversely to the longitudinal direction of the wiper blade, is adapted to the spacing distance between the two legs of the U on the free end of the wiper arm.
Advantages in the manufacture of the wiper apparatus can be obtained if both the coupling part and the pivot lever are made from a plastic.
Further advantageous refinements and features of the invention are given in the ensuing description of an exemplary embodiment shown in the associated drawing.